Part of the problem with highlights and clips is that it doesn't show the airballs and the plain embarrassing bricks. Every shooter has bad shots.
http://statsheet.com/mcb/players/player/memphis/tyreke-evans
That says he was a 27.4% shooter from the college 3 point line. He's right around that from NBA 3 point line, so I wouldn't say his shot has regressed from his college days, but it also hasn't improved significantly. That's fine. Some players who specialize at penetrating take a long time to develop a good long-range shot (Jason Kidd) and some players never develop that shot (Andre Miller). The big question is, which way will Tyreke develop. Personally, I don't think he HAS to develop an amazing jumper. I would actually prefer to see him get a good post-up midrange game to take advantage of his size and strength. Leave the 3 point bombs to the role players.